Electrical keyboard



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W. E. BLODGETT. I ELECTRICAL KEYBOARD.

No. 477,635. Patented June 28, 1892. f

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ELECTRICAL KEYBOARD. No. 477,635. Patented June 28, 1892.

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W. E. ELEOTR (No Model.)

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KEYBOARD.

No. 477,635. 6 Patented'June-ZB, 1892.

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'struction and combination hereinafter de- UNITED STATES PATENT OFFICE.

WILLIAM E. BLODGETT, OF FARIBAULT, MINNESOTA.

ELECTRICAL KEYBOARD.

SPECIFICATION forming part of Letters Patent No. 477,635, dated June 28, 1892.

Application filed March 17, 1890. Serial No. 344,074- (No model.)

To all whom it may concern:

Be it known that I, WILLIAM E. BLODGETT, of Faribault, in the county of Rice and State of Minnesota, have invented certainImprovemen ts in Electrical Keyboards, of which the following is a specification.

The object of this invention is to provide an electrical keyboard with which, by means of a small number of keys or levers, a large number of independent electrical circuits maybe closed. The electrical circuits may be used to operate the t-ypebars of an electrical type-writer, printing-telegraph, or similar apparatus,or they may be used to operate any other suitable devices.

The invention consists generally in a keyboard having a series of keys and independ ent electrical circuits with two circuit-closers in each circuit, whereby when any two of the keys are operated one of the circuits is closed, there being as many independent circuits as there are pairs of keys on the beyboard. For

instance, with a keyboard of ten keys fortyfive different pairs of keys are possible, and with such a keyboard by operating two keys at a time forty-five independent electrical circuits may be closed, and each of said circuits may be arranged to operate an independent type-bar, lever, or other device.

The invention consists, further, in the conscribed, and particularly pointed out in the claims.

In the accompanying drawings, forming a part of this specification, Figure 1 is a plan view with the keys removed, showing the electrical connections. Fig. 2 is an end elevation of the keys, showing the arrangement of the circuit-closers and showing, also, the electrical connections. Fig. 3 is a transverse section through the keys, showing the second series of electrical connections. Fig. 4 is a detail showing more than one magnet in each circuit and with a switch for throwing either set of magnets out of circuit. Fig. 5is a detail of the switch. Fig. 6 is a plan view of keyboard embodying my invention, showing operating levers or keys; and Fig. 7 is a section thereof on the line a: x.

In the drawings, 2 2 represent the keys or levers forming the keyboard. There may be any number of these keys and they may be arranged and supported in any ordinary 0r preferred manner. I prefer to employ ten keys, and these keys are preferably so arranged that the operator may place both hands upon them, allowing his fingersand thumbs to rest upon the keys all of the time, anddepress any two desired keys to operate any desired type-bar or perform any desired operation for which the machine is adapted. Each key, except one, (the last toward the right in the drawings,) is provided with a contact-point 3 and a circuit-closer 5, that is adapted to be brought in contact with said contact-point as the keyis depressed. The circuitcloser 5 is connected with a wire or conductor 7, leading to a suitable battery 9. All of the circuit-closers 5 may be connected with the same conductor 7, and thus one battery may be utilized for one entire keyboard. Contactpoints 11 are arranged in "connection with each of the keys, except the first, (toward the left,) and a conductor 13 connects each of said contact-points 11 with the first contact-point 3. A circuit-closer 15 is arranged for each of said contact-points 11, each of said circuitclosers 15 being arranged in an independent circuit 17, provided with an electro-magnet 19. The battery 9 and conductor 7 are preterably common to all of said circuits.

For the purpose of distinguishing the contact-points and circuit-closers I designate the circuit-closers 5, that are connected with the battery-wire, the initial circuit-closers and the corresponding contact-points 3 the initial contact-points, and the other circuitclosers 15 and contact-points 11 secondary. This designation is arbitrary andmadefor the purpose of clearness in description.

In Fig. 2 of the drawings I have shownthe first key at the left provided with the described initial contact 3 and initial circuitcloser 5, connected with the battery, and I i and an initial circuit-closer connected to the battery-wire for each of said keys, except means of which the circuits through all ofthe the last, and that each of said keys is provided with as many secondary contacts 11 and circuit-closers 15 as there are intial circuit-closers 3 preceding it. In other words, each key has an independent secondary circuit-closer and contact for each preceding initial circuit-closer.

It will be seen that there are in eit'ect, when ten keys are employed, forty-five independentcircuits all connected to a common battery and each having two breaks therein. By operating two keys simultaneously a single circuit will be closed, and as forty-five different combinations of two keys each can be made with ten keys it follows that any one of the forty-five independent circuits may be closed. The magnet or magnets in the closed circuit will be energized, and said magnets may be used to operate a type-bar or any other suitable device with which the keyboard I is adapted to be connected. These magnets may be located at any desired point and the circuits may be of any length. The number of keys employed may be increased or diminas it may be used in a variety of ways and supplied to various devices.

I have shown the contacts and circuitclosers in Fig.1 arranged upon a suitable board 8, having bindingposts 10, to which the wires from the magnets are connected.

In Figs. 4cand' 5 I have shown a switch by magnets 19 may be broken and an independent set of circuit through magnets 20 may be formed. By this means magnets 19 may be;

used to operate one set of devices, such as the type-bars having lower-case letters, and the magnets 20 another set, such as type-bars having upper-case letters. By moving the switch either set of circuits may be put in operative position.

The switch that I have shown consists, preferably, of a series of plates 25, insulated from each other and connected to the wires leading from the magnets. There are two sets of these plates, one connected to the wires from the magnets 19 and the other connected to the wires from the magnets 20. A lever 27 is pivoted above these plates and is connected to This lever carries at each i end a plate 29, adapted to make connection \Vhen plate 29 is the'battery-wire 7.

with all of the plates 25. in contact with one set of plates, the magnets 19 will be in use. hen it is in contact with the other set of plates, the magnets 20 will be in use. By using a suitable switch anynumber of sets of magnets may be used.

I claim as my invention- 1. The combination, with a series of keys or levers, of an initial contact-point, initial circuit-closers connected with a suitable battery and adapted to be brought in contact with said initial contact-point by the operation of one of said keys or levers, secondary contact-points for each of said other keys or levers, all connected With said initial-contactpoint, secondary circuit-closers adapted to be brought in contact with said secondary contact-points by operating said keys or levers, and independent partial electrical circuits connected with said secondary circuitclosers and each having a battery connection, substantially as described.

2. The combination, with a series of keys or levers, of a series of initial contact-points for each of said keys, except one, a correspondin g initial ci reuit-closer for each of said initial contacts, a battery connection for each of said initial circuit closers, secondary contactpoints for each of the other keys, connected with each of said initial contact-points, secondary circuit-closers for each of said secondary contact-points, and partial independent electrical circuits connected with said secondary circuit-closers and each having a battery connection, for the purpose set forth.

3. The combination, with a series of independent electrical circuits, each having two breaks therein, of initial and secondary cireuit-closers adapted to close said breaks, battery connection for each of said initial cir cuit-closers, and independent partial electrical circuits, each having a battery connection and each connected to one of said secondary circuit-closers, for the purpose set forth.

4. The combination, with a series of independent electrical circuits, each having two breaks therein, of initial and secondary circuit-closers adapted to close said breaks, battery connection for each of said initial circuit-closers, independent partial electrical circuits, each having a battery connection and each connected to one of said secondary circuit-closers, magnets in said partial circuits, an independent series of magnets, and a switch arranged to cut out one set of magnets and connect the other set with said partial circuits, for the purpose set forth.

In testimony whereof I have hereunto set my hand this 25th day of February, 1890.

A. 0. PAUL, BEss'In BOOTH.

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